Thermal Analysis, Antioxidant and in vitro Antimicrobial Activity of Palladium(II) Complexes with N,N′- Ethylenediamine Bidentate Ester Ligands

Jelena M Maskovic, Pavle Z Mas

Abstract

Palladium (II) complexes (1-4) with bidentate N,N’-ligands, O,O'-dialkyl esters (R=ethyl, n-propyl, n-butyl and n-pentyl), of (S,S)-ethylenediamine-N,N’-di-2-(4-methyl)pentanoic acid (S,S-eddp) (L1•2HCl-L4•2HCl) were prepared. The ligands and its complexes were tested for their in vitro antimicrobial and antioxidant activities. The antimicrobial activity was tested using broth dilution procedure for determination of the minimum inhibitory concentration (MIC). The MICs were determined for 6 selected indicator strains. The Pd (II) complex with the n -Pe group in ester chain displayed the strongest antimicrobial activity among the all tested compounds. The results showed that the ligand with the n -Bu group in ester chain possessed the highest total antioxidant аctivity and antioxidant activity at the level of the DPPH and ABTS radicals. The IC50 values determined were: 12.89 ± 1.75 to 8.29 ± 0.64 μg/ mL for DPPH free radical scavenging activity and 22.46 ± 1.68 to 14.46 ± 1.68 for ABTS radical scavenging assay. Also, the results of thermal decomposition have been discussed.